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Insulin and fructose regulate malic enzyme activity by different processes.

R L Drake·K M McHugh·C G Mucenski
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Abstract

A comparison of the regulatory processes controlling hepatic malic enzyme activity following treatment of diabetic rats with insulin or with a high fructose diet demonstrated several important differences. Insulin treatment caused a 50-fold increase in activity, due to a 12-fold increase in enzyme quantity and a 4-fold increase in specific activity(units/nmol). Dietary fructose caused a 3-fold increase in enzyme activity, due to a 3-fold increase in enzyme quantity, with no change in the specific activity of the enzyme. Thus, while fructose initiated a minor increase in malic enzyme activity, insulin was more effective, causing a substantially greater increase in enzyme activity and activating a hormone specific alteration in the catalytic activity of each enzyme molecule.

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AnimalsBlood GlucoseDiabetes Mellitus, ExperimentalFructoseInsulinLiverMalate DehydrogenaseMaleRatsRats, Inbred StrainsJournal Article

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R L Drake, K M McHugh, C G Mucenski. 1984-06-15. Insulin and fructose regulate malic enzyme activity by different processes.. https://doi.org/10.1016/0006-291x(84)90242-0

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